The Science Of Stress

Tania Glenn, who has a doctorate in psychology and is a licensed clinical social worker, delivered a feelings-free, scientific analysis of the human body’s physiological response to high-stress situations to a group of airmen in the United States Air Force. The goal? To help service members understand their biological processes downrange.

Glenn, who specializes in post-traumatic stress disorder in service members and first responders, described the chemical reactions that take place within the body when it experiences stress as a state of physical or emotional activation.

Biological cues trigger phenomena such as the fog of war and fight-or-flight syndrome.

In years past, fight or flight was believed to occur in seven- to 10-minute spurts very sporadically throughout the adult life. More recently, researchers and clinicians have discovered that individuals engaged in combat situations are able to maintain a state of fight or flight for months on end since it is a naturally engineered survival mechanism.

“The core element of stress, the very foundation of stress, is fight-or-flight syndrome,” Glenn said. “Without fight or flight we would not survive as a species. For members of the armed forces, this is how it works: you learn of an upcoming deployment and your energy begins to shift; you start to ramp up mentally, you disengage from your family little by little and you adopt an aggressive mindset to prepare for the hostile environment you’re going to be immersed in. As you adopt that mindset and your energy shifts, you begin to produce more adrenaline, glucose and cortisol, which are the very basis of the fight-or-flight response.”

Therefore, individuals who are exposed to high-threat situations that require their bodies to enter into a no-holds-barred state of fight or flight for an extended period of time are more likely to experience unpleasant symptoms, similar to withdrawal, upon returning to an environment with nonthreatening conditions.

“As you start to come down from fight or flight, you may feel a sense of agitation – an ants in your pants feeling that you can’t shake,” Glenn said. “You’re tired, but you can’t sleep; you want to sit still, but you are compelled to get up and move. Your body is literally detoxing from exhilaration. It’s readjusting to normal conditions after being on an adrenaline rush for weeks, months at a time. And just like any detox, coming off the extra adrenaline, glucose and cortisol is unpleasant.”

In direct contrast to fight-or-flight syndrome, what Glenn refers to as “the freeze” can also take place during intense or hostile situations. Though individuals who find themselves rooted to the spot in combat situations are often regarded as cowardly, this reaction can be attributed to chemical processes that take place within the brain, completely independent of conscious decision.

“The freeze is basically the untrained brain and the passive personality,” Glenn said. “Instead of dumping adrenaline, glucose and cortisol — the chemicals that make you fast and strong — the brain dumps useless neurotransmitter fluids and renders you virtually frozen, unable to move or activate.”

Likewise, the brain can also be held responsible for causing knee-jerk bodily functions such as shaking and vomiting during, or following, traumatic events.

According to Glenn, there are many overt physiological reactions that transpire during an acute, or incident prompted stress reaction.

Physiological reactions occur when an individual launches into fight or flight prompting the system to focus solely on survival. This transition sets off a chain reaction beginning when the brain directs blood flow away from the extremities toward the core, thereby oxygenating the heart, lungs, major muscles, back and legs. This, Glenn said, allows for maximum running and striking power, but markedly diminishes fine motor function.

Once the danger has passed, the diversion of blood flow coupled with exponentially increased levels of adrenaline raging through the system manifest as uncontrollable shaking.

To give the body still more fight-or-flight ability, the brain directs the digestive track to come to a halt, stopping what it deems an unnecessary expenditure of calories and energy. This survival measure can leave an individual feeling nauseous. In some cases, the digestive track will also be flooded with fluid to rid itself of food that may be preventing optimum speed and performance — the end result of which is vomit.

Acute stress reactions also cause the heart to beat inordinately fast, reaching speeds between 180 and 200 beats per minute. This activity sends off a signal to the brain’s thought processing and decision making center, the prefrontal cortex, to shut off. In its place, the midbrain, what Glenn refers to as the kill or be killed portion of the brain, kicks into high gear. During this time, all functioning is determined by instinct and training.

Many who experience this chemical process cannot recount their thought processes or successfully analyze situations for a period of time following the event. This is the fog of war, Glenn said.

During the 90-minute briefing, Glenn went on to break down the four types of stress, explaining the physiological reasons for each and the body’s natural reaction to the strain.

Though based out of Austin, Texas, Glenn travels cross-country providing respite to service men and women who bear the physical and emotional scars that accompany more than a decade of war. Though she is an accomplished psychologist, Glenn is clear on one point: the “F-word:” Feelings. Feelings shall be referred to most sparingly and only when completely necessary, she said.

“I’m a boots-on-the-ground kind of person and we don’t use the F-word,” she joked. “I talk about the brain and the body and what happens during trauma and stress. These reactions have nothing to do with feelings, they’re about survival. I work every day to help men and women recover from trauma and PTSD because if there’s one thing I can’t stand, it’s seeing warriors suffer.”

By Senior Airman Whitney Tucker27th Special Operations Wing Public Affairs, from www.af.mil

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